[PATCH] PR fortran/42546 -- ALLOCATED has 2 mutually exclusive keywords

[Steve Kargl <sgk at troutmask dot apl dot washington dot edu>]

The attached patch fixed the issues raised in the
PR fortran/42546.  Namely, ALLOCATED has two possible
keywords: ALLOCATE(ARRAY=...) or ALLOCATED(SCALAR=...)

In Tobias' original patch (attached to the PR), he 
tried to make both ARRAY and SCALAR options, then 
in gfc_check_allocated() appropriate checking was
added.  I started down that road, but intrinsic.c(
sort_actual) got in the way.  Fortunately, the 
checking for ARRAY or SCALAR can be special-cased
in sort_actual.  See the patch.

Regression tested on x86_64-*-freebsd.  OK to commit?

2019-08-01  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/42546
	* check.c(gfc_check_allocated): Add comment pointing to ...
 	* intrinsic.c(sort_actual): ... the checking done here.
 
2019-08-01  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/42546
	* gfortran.dg/allocated_1.f90: New test.
	* gfortran.dg/allocated_2.f90: Ditto.

-- 
Steve

Index: gcc/fortran/check.c
===================================================================
--- gcc/fortran/check.c	(revision 273950)
+++ gcc/fortran/check.c	(working copy)
@@ -1168,6 +1168,10 @@ gfc_check_all_any (gfc_expr *mask, gfc_expr *dim)
 }
 
 
+/* Limited checking for ALLOCATED intrinsic.  Additional checking
+   is performed in intrinsic.c(sort_actual), because ALLOCATED
+   has two mutually exclusive non-optional arguments.  */
+
 bool
 gfc_check_allocated (gfc_expr *array)
 {
Index: gcc/fortran/intrinsic.c
===================================================================
--- gcc/fortran/intrinsic.c	(revision 273950)
+++ gcc/fortran/intrinsic.c	(working copy)
@@ -4180,6 +4180,40 @@ sort_actual (const char *name, gfc_actual_arglist **ap
   if (f == NULL && a == NULL)	/* No arguments */
     return true;
 
+  /* ALLOCATED has two mutually exclusive keywords, but only one
+     can be present at time and neither is optional. */
+  if (strcmp (name, "allocated") == 0 && a->name)
+    {
+      if (strcmp (a->name, "scalar") == 0)
+	{
+          if (a->next)
+	    goto whoops;
+	  if (a->expr->rank != 0)
+	    {
+	      gfc_error ("Scalar entity required at %L", &a->expr->where);
+	      return false;
+	    }
+          return true;
+	}
+      else if (strcmp (a->name, "array") == 0)
+	{
+          if (a->next)
+	    goto whoops;
+	  if (a->expr->rank == 0)
+	    {
+	      gfc_error ("Array entity required at %L", &a->expr->where);
+	      return false;
+	    }
+          return true;
+	}
+      else
+	{
+	  gfc_error ("Invalid keyword %qs in %qs intrinsic function at %L",
+		     a->name, name, @a->expr->where);
+	  return false;
+	}
+    }
+
   for (;;)
     {		/* Put the nonkeyword arguments in a 1:1 correspondence */
       if (f == NULL)
@@ -4199,6 +4233,7 @@ sort_actual (const char *name, gfc_actual_arglist **ap
   if (a == NULL)
     goto do_sort;
 
+whoops:
   gfc_error ("Too many arguments in call to %qs at %L", name, where);
   return false;
 
Index: gcc/testsuite/gfortran.dg/allocated_1.f90
===================================================================
--- gcc/testsuite/gfortran.dg/allocated_1.f90	(nonexistent)
+++ gcc/testsuite/gfortran.dg/allocated_1.f90	(working copy)
@@ -0,0 +1,24 @@
+! { dg-do run }
+program foo
+
+   implicit none
+
+   integer, allocatable :: x
+   integer, allocatable :: a(:)
+
+   logical a1, a2
+
+   a1 = allocated(scalar=x)
+   if (a1 .neqv. .false.) stop 1
+   a2 = allocated(array=a)
+   if (a2 .neqv. .false.) stop 2
+
+   allocate(x)
+   allocate(a(2))
+
+   a1 = allocated(scalar=x)
+   if (a1 .neqv. .true.) stop 3
+   a2 = allocated(array=a)
+   if (a2 .neqv. .true.) stop 4
+
+end program foo
Index: gcc/testsuite/gfortran.dg/allocated_2.f90
===================================================================
--- gcc/testsuite/gfortran.dg/allocated_2.f90	(nonexistent)
+++ gcc/testsuite/gfortran.dg/allocated_2.f90	(working copy)
@@ -0,0 +1,16 @@
+! { dg-do compile }
+program foo
+
+   implicit none
+
+   integer, allocatable :: x
+   integer, allocatable :: a(:)
+
+   logical a1, a2
+
+   a1 = allocated(scalar=a)   ! { dg-error "Scalar entity required" }
+   a2 = allocated(array=x)    ! { dg-error "Array entity required" }
+   a1 = allocated(scalar=x, array=a)   ! { dg-error "Too many arguments" }
+   a1 = allocated(array=a, scalar=x)   ! { dg-error "Too many arguments" }
+
+end program foo